Edwabd weston



(No Model.)

E. WESTON.

ELECTRICAL SWITCH.

No. 340,401. Patented Apr. 20, 1886.

- INVENTOR,

N, PETERS. Pholwlfllwgnpher, Washington. D. C.

EDWARD WESTON, OF NEWARK, NEW

JERSEY, ASSIGNOR TO THE UNITED STATES ELECTRIC LIGHTING COMPANY, OF NEW YORK, N. Y.

ELECTRICAL SWITCH.

SPECIFICATION forming part of Letters Patent No. 340,401,

dated April 20, 1886.

Application filed December 5, 1885. Serial No. 184,795. (No model.)

To all whom it may concern:

Be it known that I, EDWARD WESTON, a subject of the Queen of Great Britain, resident of Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Electrical Switches, of which the following is a specification, reference being had to the drawings accompanying and forming a part of the same. y

v switch invented by me I cut No. 316,096, dated April 21, 1885, and in other patents granted to The United States I 5 Electric Lighting Company as my assignees.

The improvement is applicable to an obvious modification of the form of switch shown and specifically described in the said patent, such modification consisting in the combination of two stationary contacts, two springs between the same and normally out of contact therewith, and an insulating block orcam, preferably capable of a limited movement around the spindle,placed between the springs and adapted to force the springs against the contacts or permit them to recede therefrom with a sudden movement or snap.

Inthisdevicetheinsulating-camrubs against the springs and in a short time its sides be;

come coated with a thin film of metal, which is worn off from the metal springs. This I have found is liable to destroy the switch by forming a short circuit between the springs, through which a high-tension current finds a ready path.

- My present improvement invention is an improvement on the and described in Patconsists in forming deep grooves or slots in the faces or sides of the insulating block or cam, whereby the metallic surface which tends to form is interrnpted and short-circuiting entirely prevented. This is shown in the accompanying draw- Figure 1 is a-diagram showing the circuits and incandescent lamp and the arrangement of the switch. Fig. 2 is a side elevation of the switch spindle and cam. Fig. 3 is a crosssection through the cam.

A B are the two stationary contacts. They maybe placed in any convenient form of socket or lamp-holder, or may be used for any other form of electrical device.

G D are the contact-springs, tween the plates A B.

E is a spindle mounted between springs O D. On it is a block or cam -shaped piece, F, of insulating material, secured to the spindle by a pin, 0, set in the spindle and extending through the slot f in any part of the cam. The cam is conveniently made nearly rectangular in cross-section,with rounded or beveled corners, so that when turned by the spindle it will be thrown around by the force of the springs as soon as it is turned until the corners alone touch the springs. In the cam are formed arranged bedeep grooves or slots G G in each face, or in the wider faces only.

In using the switch the faces of the cam are constantly rubbing against the springs, and a metallic surface is soon formed. The slots or grooves interrupt this surface, however, and prevent short-circuiting. In this way I make the switch a safe and practicable device.

What I claim is- 1. In a switch or circuit-controller, the-combination, with contacts and circuit-terminal springs, of a spindle and insulating-cam for forcing the springs against the contacts, the

cam being provided with grooves or slots in its faces, as and for the purpose set forth.

2. In a switch or circuit-controller, the combination, with contacts and circuit-terminal springs, of a spindle and insulating-cam capable of a limited movement on said spindle and adapted to bring the springs into or out of engagement with the contacts, the cam being provided with grooves or slots in its faces, as and for the purpose specified.

3. The combination of stationary contacts, spring-terminals between the same, and aspindle and insulating-cam between the springs, for making and breaking contact between said springs and the stationary contacts, the said cam being provided with grooves or slots in its faces, as and for the purpose specified.

EDWARD WESTON.

Witnesses:

HENRY A. BECKMEYER, BAXMQND F. BARNES. 

